Method of and machine for producing



1956 A. D. SIMPSON 31,889

METHOD OF AND MACHINE FOR PRODUCING CONTINUOUS STRIPS OF FIBROUS SHEET MATERIAL Filed May 11, 1951 8 Sheets-Sheet l A. D. SIMPSON ACHINE FOR PRODU METHOD OF AND M CING CONTINUOU STRIPS OF FIBROUS SHEET MATERIAL 8 Sheets-Sheet 2 Jan. 24, 1956 Filed May 11, 1951 Jan. 24,, 1956 METHOD OF AND 2,731,889 E FOR PRODUCING CONTINUOUS 8 Sheets-Sheet 3 Filed May 11, 1951 Jan. 24, 1956 SIMPSON 2,731,889

METHOD OF AND MACHINE FOR PRODUCING CONTINUOUS STRIPS 0F FIBROUS SHEET MATERIAL Filed May 11, 1951 8 Sheets-Sheet 4 Jan. 24, 1956 Filed May 11, 1951 SIMPSON A. D. 2,731,889 METHOD OF AND MACHINE FOR PRODUCING CONTINUOUS STRIPS OF FIBROUS SHEET MATERIAL 8 Sheets-Sheet 5 A. D. SIMP MACHINE FOR STRIPS 0F FIBROUS SON 2,731,889 PRODUCINGICONTINUOUS SHEET MATERIAL Jan. 24, 1956 METHOD OF AND 8 Sheets-Sheet 6 Filed May 11, 1951 1956 A. D. SIMPSON 2,731,889

METHOD OF AND MACHINE FOR PRODUCING CONTINUOUS STRIPS OF FIBROUS SHEET MATERIAL 8 Sheets-Sheet 7 Filed May 11, 1951 Jan. 24, 1956 A. D. SIMPSON 2,731,889

METHOD OF AND MACHINE FOR PRODUCING CONTINUOUS STRIPS OF FIBROUS SHEET MATERIAL Filed May 11, 1951 8 Sheets-Sheet 8 United States Patent TR-lPS OF FIBRQUS SHEET MA- Alvan 1). Simpson, Plainfieid, N. 5., assign-or to The arm ing Machine Company of America, hm, Bound Brook, N. 1-, a rpo a i n of De aw re Application May 11, 1951, Serial No. 225,878 Claims.v (Ci. 92-43) This invention relates in general to the manufacture ofcontinuous strips or webs formed by the deposit on a travehng surface of, for example, a wet mix comprising asbestos-fiber and cement; and the invention also contemplates the application to such sheet material of surfacing substances such as liquid or semi-liquid compositions, or granules.

in a known machine that is in use for producing films or strips of asbestos-cement composition, the composition is deposited by scre n cylinders from vats as a thin film upon a traveling felt belt which after receiving such deposit is moved under and into contact with an accumulator cylinder which picks the film from the belt and winds it in several layers or laminations on the cylinder, creating a so-called laminated finished product. When the desired thickness of laminated product is accumulated on the cylinder, the material is slit lengthwise of the cylinder so that the material falls from the cylinder as a sheet. This strip contains a substantial amount of water; and it must be passed through a hot gas or oil oven to remove some of the water before the strip can be roll pressed at even low pressures to finish it. Moreover, in applying a veneer or surfacing substance to the film, such substance is deposited by a screen cylinder-from another vat onto the film at the proper moment so that the veneered face of the film is next to the accumulator roll.

Thatmethod is objectionable in that the veneer or surfacing substance doesnot adhere firmly to or interlock with the film or base web, as a consequence of which the veneer or surfacing substance often peels off or sticks to press rolls when attempts are made to roll-press the veneered film or web to make for example shingles. Another objection to that old method is that the screen leaves its mark on the top surface of the veneer so that it is extremely difiicult not impossible to obliterate the said mark even when the film or web is subjected to roll pressure.

Attempts have been made to apply a granular deposit to the film or Web after it has been removed from the accumulator roll; and then to pass the webthrough a roll press; but this method is defective in that the granular deposit injures the webas. the granules are forced into it by. the roll press and the granules do not become interlocked with the web, with the result that when the web is turned upside down a large percentage of the granules fall from it.

Therefore, a prime object of the present invention is to provide amethod of and machine for applying a veneer or surfacing substance in anovel and improved manner such that the veneer or surfacing substance shall be firmly interlocked with orbonded to the base film or webagainst accidental dislodgment or'peeling off, and without defacement of the face of the web,

The invention is especially intended for use in connection with a method and machine of'the type disclosed in theapplication of AlvanD. Simpson, SerialNo. 24,054, filed April 22, 1948, now Patent No, 2,581,210, wherein 7 2,731,889 Patented Jan. 2 4, 1956 a perforate drum is rotatable about a horizontal axis within a tank with a portion of its periphery submerged in a wet mix, and means is provided for supplying air at a pressure substantially above atmospheric pressure to. the surface of the mix and to a portion of the periphery of the drum above the level of the. mix, the casing having an opening for the withdrawal of the deposited strip through which a portion of said drum is exposed, and the space between the edges of which and the drum is sealed to prevent escape of the mix and air pressure from the. casing. In that machine, the liquid from. the is forced through the perforate drum and the solid matter is deposited on the outer surface of the drum, after which the deposited layer is moved: out of the mix into the high pressure zone above the drum so that the air pressure forces the liquid from the deposited layer, whereupon the layer is removed from the drum through said openmg.

Another feature of the invention is the roll pressing of the deposited layer in said high pressure zone so as to provide for substantial roll-pressing of the film directly in the machine and also drying of the film sufficiently' toallow additional roll-pressing after the film leaves the machine if that is required. This will eliminate the necessity of passing the layerof film through a hot gas or oil oven and then roll pressing the steaming film as is required by the old method, and at the same time will eliminate any injury to the layer from heating and the expense incident to the successive depositing, heating, and roll pressing operations. Also, with the invention, the roll pressing at substantial pressures permits the strength of the film to beincreased bypressure instead of by the use of premium and expensive mixes or formulas which. are necessary with the present machines.

Another object of the invention is to provide a novel and improved method consisting of applying a surfacing substance such as a veneer mix or granular material to such a deposited layer while said layer is in said high pressure zone, forcingv said surfacing substance firmly into the pores of' the deposited layer without rupture of the surface of the layer and thereafter closing said pores around the particles of the mix or the granules.

Further objects. of the invention are to provide novel and improved means. for supplying asurfacing substance such as a veneer mix tov such a deposited layer, and to provide means. for firmly pressing the surfacing substance into the. pores of said deposited layer.

The invention contemplates a vat or tank for supply ing the, surfacing substance. to. the layer continuously as the layer ismoved by the, drum, and the mix is Wet and abrasive; and another object of the invention isto provide a novel and improved; vat including relatively movable parts to compensate; for variations. in thicknessof the-deposited layer and means for mountingthe vat in the tank with respect to, the depositing: drum, whereby veneers may be easily applied with; a min' um, of leakage and abrasion between the relatively movable parts of; the vat and between said parts and said drum.

Other objects, advantages and results ofthe invention will be brought out by the following description. in con j n n h. t a ompany g;- aw ng in Whi h.-

Figure 1 is an end elevational view of a machine, for making continuous strips. ofmaterial from a wet mix, including means for applying the surfacing substances to the strip; V

Figure 2 is a vertical longitudinal. sectional view through the machine taken approximately on the. plane of the line 2 2 of Figure 1;

Figure 3 is atransverse vertical sectional view taken approximately on,the planeof the line,3-3 of Figure 2;

Figure 4 is an enlarged fragmentary plan view from zontal view approximately on approximately the plane of the line 4-4 of Figure 3;

Figure 5 is an end elevational view of the parts shown in Figure 4;

Figure 6 is a horizontal sectional view approximately on the plane of the line 6-6 of Figure 5;

Figure 7 is a transverse vertical sectional view approximately on the plane of the line 7- 7 of Figure 4;

Figures 8 and 9 are enlarged fragmentary sectional views on the respective planes 3-% and 9-9 of Figure 3;

Figure 10 is an enlarged fragmentary vertical sectional view approximately on the plane of the line lib-1i) of Figure 1;

.Figure 11 is an enlarged horizontal sectional view approximately on the plane of the line 11-41 of Figure 3;

Figure 12 is a similar view approximately on the plane of the line 12-12 of Figure 3;

Figure 13 is a horizontal sectional view approximately on the plane of the line 13-13 of Figure 1;

Figure 14 is a similar view approximately on-the plane of the line 14-44 of Figure 10;

Figure 15 is an enlarged fragmentary vertical horithe plane of the line 15-15 of Figure 3 showing the pressing of the deposited layer at the lowermost or first roller above the mix level at the exit side of the drum;

Figure 16 is asimilar view at veneer mix is applied;

Figure 17 is a like view at the next roller; and

Figure 18 is a similar view on approximately the plane of the line 181S of Figure 3.

For the purpose of illustrating the principles of the invention, it has been shown in conjunction with a machine of the type disclosed in the co-pending applications of Alvan D. Simpson, Serial No. 24,054, filed April 29, 1948, and Serial No. 217,906 filed March 28, 1951, said machine including a tank or casing A that has an inlet 1 for a wet mix 2 of a suitable composition of matter, for example an asbestos cement composition such as is commonly used in the manufacture of building shingles, sidings and the like. This mix may be of any suitable consistency, and generally comprises solid particles, such as asbestos fibers and cement, suspended in water; and the the next roller where the in any suitable manner, preferably under pressure.

Rotatably mounted about a horizontal axis in the tank is ahoilow cylindrical rotor drum or cylinder having solid end walls of plates 3 from which project coaxial tubular trunnions 4. and a perforate peripheral wall 5, which may comprise a screen 6 and a supporting plate 7, connecting said end walls. The structure of the drum may be as desired, for example as described in said application Serial No. 217,906; and secured to the side plates 3 and projecting coaxially beyond the perforate wall 5 are end rings 8 that form inwardly facing shoulders 9 disposed in a plane perpendicular to the axis of rotation of the drum and which preferably have a resilient wear resisting covering such as that described in said application.

The drum is located in the tank so that a lower portion thereof will be submerged in the mix in the lower portion of the tank, as best shown in Figures 2 and 3, and the drum may be rotatably mounted in any suitable manner as by jcurnaling the trunnions 4 in bearings 11 that project upwardly from a base 12 on which the tank is mounted, one of the trunnions being connected by a gear train 13, 14 to a drive shaft 15 which may be connected to any suitable source of power as by a belt and pulley 16.

With this construction, when the drum is rotated through the mix 2, the liquid from the mix will flow through the interstices in the screen 6 so as to cause a deposit of some of the solid matter in the mix on the screen, and as the drum continues to rotate, this deposited solid matter is elevated out of the mix into the upper portion of the tank where the liquid drains from the deposited layer downwardly into the drum from ferential wall of the tank to bring this deposited mix may be supplied into the tank through the inlet 1 suitable mounting structure D whence the liquid is drained 01f through the hollow trunnions 4 by any suitable means such as a drain pipe 17 that extends through the hollow trunnions and has one end closed and the other end connected as by a hose 13 to a suitable pump. The pipe 17 has a branch 19 depending between the end plates 3 of the drum into the lower portion of the drum so that liquid may be withdrawn from the drum through said branch into the drainpipe and thence to a suitable discharge point. The layer of solid matter that is disposed on the periphery of the drum is removed through an opening 20 in the circum-t above the level of thernix, Air or other suitable gas under pressure substantially in excess of atmospheric pressure, for example at from fifteen to one hundred pounds pressure, is supplied to the tank A above the level of the mix, for example from a suitable pump through a pipe 21. This pressure continuously exerted on the surface of the mix tends to accelerate the flow of drum and at the same time to force the liquid from the deposited layer on the upper portion of the drum and thereby form open pores on the layer.

More specifically describing the operation of the machine, the mix is fed into the tank A until the level rises above the roller E at the'lower edgeof the opening 20. The water showers or sprays are turned on and the rotor drum is started to revolve. As the mix contacts the drum, a very light or thin film of the solid matter in the mix' is deposited on the screen because of the small difference in level between the mix in the tank and the water within the rotor drum. When the drum is rotated sufficiently film under the roller C at the upper edge of the opening 29, the compressed air is supplied through the pipe 21 into the space in the tank above the rotor drum and the mix. The film on'the drum prevents the escape of this air through the drum and the opening 20, ancl'as the pressure builds up in said space, the air pressure causes the film to become thicker due to the acceleration of the flow of the liquid from the mix through the perforate drum; and as this film becomes thicker and better seals the screen 6 on the portiontof the'drum above the mix, it is possible to increase the air pressure above the drum. In this manner, the machine is brought to normal operation and the gas pressure, speed of the rotor drum and the mix concentration, are all adjusted so as to deposited layer at thedesired production rate. it should be noted that the compressed air in the space above the drum slowly works its Way through the deposited layer on the screen 6 and thus forces the excess water out of said layer; and due to the. heavy pressure and the relatively smallarea, there is a marked drying effect.

Any suitable means may be provided for preventing leakage through said opening 20 of both the wet mix and such air or gas pressure. One suitable sealing means is shown in said application Serial No. 217,906. As shown in Figures 1 and 3, a sealing roller C is journaled in a (to. be hereinafter more fully described) adjacent the upper end of the opening 20 with its periphery in tight contact with the deposited layer on the screen 6 on the drum and adjustable toward and from the drum. At the other or lower end of the opening 20 is a similar roller E journaled in a mounting structure F that is identical with the structure D, the periphery of said roller contacting with the screen 12 at or preferably below the level of the mix and adjustable toward and from said screen.

The rollers C and E cooperate with the shoulders 9 on the drum to form a part of said sealing means, and preferably the end surfaces of the rollers or said shoulders or both are covered with a suitable resilient friction resisting material, for example rubber or neoprene. As hereinbefore described, the shoulders 9 have a covering, and the rollers C and E which may with the same or similar material. Furthermore, in acliquid from the'mix through the give the required thickness of the' be identical are also covered cordance with the, invention t e rollers C and E preferably are lengthwise adjustable,or arelongitudinally extendable and contractable so as to obtain and maint'ain proper contact between the rollers and said shoulders of the drum; and the contact between the roller and the drum is maintained under pressure greater than the pressure inside the tank. i V i V The sidewalls of the tank A have two arcuate portions 22 and 23 the latter of which is of smaller diameter than the portion 22, said arcua te portions being connected by approximately radial portions 24. The opening 29 extends through the length of the arouate portion 23 and has its end portions extending each of the radial Wall portions 24. V i i For sealing the junctions between the walls of the tank, and the rollers and drum, a sealing element G formed of rubber, neoprene or other suitable material is in the form of an elongate generally rectangular ring having end portions extending longitudinally of the rollers C and E in fluid-tight contact with the peripheral surfaces thereof, and also having portions in fluid tight contact with the end surfaces of said rollers. The side portions of the sealing element are in fluid tight contact with the peripheral surfaces of the rings 8 'of the drum as shown in Figures 3 and 9. The sealing element is mounted in a holder l-l which is channel-shaped in cross section and has side portions connected to the edges of the opening 20 in the arcuate wall portion 23 as shown in Figure 9, the end portions of the holder being fastened in fluid tight relation to the bracket plates 25 Each roller C and E is either formed of or coated with elastic material so that its end surfaces will form fluid tight contact with the shoulders 9 of the drum (see Figures 3 and 9); and each roller has a shaft 26 journaled in hear.- ing sleeves 27 that are roekably mounted on trunnions 28 in bifurcated bearing blocks 29 which are reciprocable in a guide frame 30 which is in turn mounted in any suitable manner on the tank A. As shown, the frame 30 has arms 31 pivotally connected at 32 to the tank and normally held by suitable releasable locking means 33 in the position to properly locate the roller with respect to the periphery of the drum B. A fluid pressure motor 34 is carried by the frame 36 and connected by a piston rod 35 and a cross head 36 to the bearing blocks 29 for normally pressing the rollers into contact with the deposited layer on the drum or with the screen, as the case may be.

The rollers C and E and the sealing element G thus completely seal the opening 20. so that when there is a deposited layer I on the drum, the pressure in the tank may be several times greater than atmospheric pressure. The upper roller C also cooperates with a stripper plate 37 for guiding the deposited layer J off the drum.

When the rotor lifts the film above the mix level, the high pressure gas works its way through the film forcing the excess Water out through the microscopic pores or channels in the film. After the excess water is forced from the pores, the empty pores or channels form voids and the film is passed under one of a plurality of presser rolls in the high pressure zone above the drum to close up said pores. After passing under one of the presser rolls, which may be like those hereinafter described, the film is again acted on by the high pressure gas and again excess water is forced through the pores and those pores are again closed up by the, next presser roll. This can be repeated until the film is dried and roll-pressed to any desired degree, depending only on the sizefof the machine.

Another i. portant feature of the invention is the application of a surfacing substance such as a veneer, coating or granular material to the deposited layer while said layer is subject to the high gas pressure in the upperportion of the tank. The veneer may be a wet mix of cement, water and suitable coloring matter, or a semi-liquid. coating of tabl color a d a lar ma er a ma be crushed stone, slate or the like.

The apparatus for applying the veneer or other liquid or semi-liquid deposit or coating on the layer J on the drum is shown as comprising a vat that includes two spaced and opposed side wails each comprising a metal plate 33 (see Figure 6) having a liningv ofrubber, neoprene, or the like one edge of which is arcuately curved on a radius corresponding to that of the peripheral surface of the drum shoulder and nicely frictionally engages one shoulder surface with a liquid tight joint. The inner surface of each lining 39 adjacent another edge thereof frictionally contacts with one end of a roller 40 which is formed of or is coveredby rubber or other suitable resilient and abrasive resisting material like the lining 39.. These two side plates are yieldingly held in liquid-tight contact with the ends of the roller 40 by any suitable means such as U-shaped spring bars 41 that straddle the side walls and have their ends in abutting contact with the wails as indicated at 42. The vat also has an end Wall comprising a metal plate 43 slidable in a frame 43a and having a resilient wear resistant lining 44 one edge of which is in frictional contact with the periphery of the roll 4% as best shown in Figure 7, said end wall being vertically movable to compensate for the movement of the roll 4% that is required to accommodate variations in the thickness of the layer J. Resilient corner sealing elements 45 bridge the joints between the side plates and the end plate to provide a leak-pr0of construction.

The side walls of the vat are mounted for limited free movement in their own planes to permit accurate contact of the linings 39 with the depositing drum, and as shown eaeh plate is pivotally connected by a link 46 to a bearing 47 that is rigidly mounted on a guide frame 48 which is rigidly mounted on the interior of the tank wall 22 for guiding the roll 4%). Excessive movement of the end walls away from the drum under the influence and in the direction of rotation of the roll 46, is prevented by a stop lug 49 carried by the link 46 to abuttinglyengage the frame 48. A tie rod 56 assists in holding the side walls in proper relation to each other.

The roll 45) constitutes in effect one side of or a portion of the bottom of the vat and normally is held in tight contact with the outer surface of the deposited layer J on the drum. The roll is shown as journaled in hearing blocks 51 that are slidably mounted in the guide frame 48 and have actuating rods 52 extending through packing glands 53 in the tank wall 22 and connected to a cross head 54 which is in turn connected to the piston rod 55' of a fluid pressure motor 56. With this construction, the roll 46 is mounted and operates in substantially the same way as the roller C.

in operation of the apparatus so far described, the veneer mix K is supplied to the vat from any suitable source, for example through a supply pipe 57 from a hopper or tank 58 under control of an inlet valve 59 operated by a float 60 in known manner. The roll 40 is held by the motor 56 in tight contact with the deposited layer l and the mix in the vat rests by gravity against the deposited layer 3. As the deposited layer is moved by the drum beneath the roll 49 in the high pressure space, some of the veneer mix is deposited on or adheres to the layer 3 to form a veneer or coating layer L. The two layers J and L then pass beneath one or more presser rolls 61 that are pressed tightly against the veneer layer, for example by fiuid pressure motors 62 mounted on the outside of the tank A and having their piston rods 63 connected by cross heads 64 to actuator rods 65 descending through packing glands 66 in the tank walls and carrying bearings 67 in which the shafts 63 of the rollers are journaled (see Figures 3 and 8). Suitable scrapers 6? may be provided for removing any impurities the roll may pick up from the mix or film, and of course the rubber lining 44 of the end Wall of the vat will scrape the veneer mix from the periphery of the roll 40.

Another roll 70 identical with and mounted in the same manner as the rolls 6!. may be arranged to engage the deposited layer immediately above the wet mix" in the tank A so asto' smooth the deposited layer preliminary to the application of theveneer mix thereto.

An important feature of the invention is the application of a surfacing substance such as a veneer mix, liquid coating of' granular materials to the deposited layer in the high pressure zone because I have discovered that by doingso the surfacing substance can be firmly interlocked with'or bonded to the layer without defacement of the face of said layer and'with a minimurn' of possibility of the surfacing substance being dislodged or peeling off. It has been found that as the deposited layer enters the high pressure air zone above the level of ti wet mix in the tank A, the compressed air forces most of the water out of the layer so as to leave minute pores in the layer. The surfacing substance being wet easily enters these pores and is firmly forced into them by the high gas pressure above the layers, which also forces the water out of the veneer and through the'screen on the drum; and when the two layers are moved beneath the presser rolls 61', the surfacing substance, is further pressed and interlocked with the base layer 3 and the pores of the base layer are closed up tightly around the surfacing substance. This is particularly important where the surfacing substance is granular, because the pores freely receive the granules without injury to the surface of the deposited layer and the deposited layer is firmly pressed around the granules in the pores so that the granules are firmly bonded to the deposited layer.

The bonding of the veneer mix and granules is illustrated in Figures to 18 inclusive where Figure 15 shows the smoothing and compressing action of the first roller 79 on the deposited layer as the latter is raised from the wet mix in the tank. Figure 16 shows the further compression and smoothing of the deposited layer by the roll 40 at the vat, while Figure 17 shows the manner in which the first roll 61 above the vat presses the veneer mix onto the deposited layer I before the granules have been applied. Figure 18 shows veneer mix or other surfacing substance pressed into the pores of the deposited layer and firmly bonded with the layer as the finished strip passes beneath the roller C. Granular materials, either wet or dry, may be dropped by gravity onto the deposited film or layer instead of being laid or spread on said layer as is required with a wet veneer mix or liquid coating substance. tight housing M may be mounted on the top of the tank A with a hopper 71 therein for the granular material, the housing having a filling pipe '72 through which the granular material may be supplied to the hopper. granules are discharged or released from the hopper by a known type of vibratory base plate feeder 73 that is actuated by a known type of electrical vibrator 74. The discharge end of the feeder plate 73 is disposed above and in alignment with a discharge chute 75 that leads from the housing to a point above the drum B so that the granular material will be dropped by gravity from the feeder plate through the chute upon the surface of the deposited layer I as best shown in Figure 3. The point of application of the granules to the deposited layer is such that the layer with the granules thereon will pass beneath at least one of the presser rolls so that the granules will be firmly pressed into the deposited layer while the latter is in the high pressure zone of the tank.

The compressed air forces the water in the film through its microscopic pores into the interior of the rotor. This dries the film and the pores or channels through the film have the water removed from them. Therefore, when the granules are forced into the film by a roll, the space or volume for the granules is obtained by closing up some of the pores or channels. This prevents the forcing of the granules into the film from cracking or injuring the film; and the absence of water from the layer makes it possible to firmly press the material of the layer tightly around the granules.

Preferably the housing M will have sight openings 76 For sodepositing the granular material, an air-' and electric lamps 77 so located that the action of the granule feeder may be observed; and also the main tank A may have sight openings 78 and electric lamps 79 through which the condition of the veneer and the operation of the presser rolls may be observed. t 7

rom the'foregoing, it will be seen that the method which consists in applying the surfacing substance to the layer after the major portion of the Water has been forced from the layer, and particularly while the layer is in the high pressure zone ofthe tank, strikingly and unexpectedly makes possible a firmbonding of the surfacing substance with the deposited layer and without rupture or other defacement of the face of the layer; and that while the method has been described as consisting of certain steps and one embodiment of the machine has been illustrated, the steps of the method may be varied and the structure of the machine may be widely modified and changed within the spirit and scope of the invention.

It will also be understood that other devices and accessories maybe added to the machine where desirable; for example, any suitable device other than the fioat valve shown may be utilized for controlling the supply of veneer mix to the vat, and jets of water may be directed against the ends of the roll 4%) outside of the vat for cleaning said ends of the abrasive material and thereby reducing the wear of the frictionally engaging surfaces of said roll, the side plates of the vat and the shoulders of the drum.

I claim: r

l. The method comprising separating and forming a strip of solid materials from a mix of the order of liquid having cement and fibers in suspension, moving said strip while the strip is wet through a pressure chamber with one side exposed to the atmosphere and the other side subjected to a gas pressure substantially above atmospheric pressures to force liquid from said strip and form pores in said strip, and spreading a layerof a wet mix of a surfacing substance on the second-mentioned side of said strip while the strip with said layer of surfacing substance thereon is moving through said pressure chamber thereby causing said surfacing substances to flow into said pores. V

2. The method comprising separating and forming a strip of solid. materials from a mix of the order of liquid having cement and fibers in suspension, moving said strip while the strip is wet through a pressure chamber with one side exposed to the atmosphere and the other side subjected to a gas pressure substantially higher than atmospheric pressures to force liquid from said strip and form pores in said strip, and spreading a layer of a wet mix of a surfacing substance on the second-mentioned side of said strip while the strip is soft and moist and maintaining said layer of surfacing substance under said higher pressure.

3. The method comprising separating fibrous material from a liquid which has held it in suspension and forming a strip thereof, subjecting one side of said strip while the strip is wet to gas pressure with the other side subject to a lower gas pressure to remove liquid from and form open pores in said strip, and depositing granules upon the first-mentioned side of the strip, while maintaining said strip and said granules subject to said gas pressures.

4. The method comprising separating fibrous material from a' liquid which has held it in suspension and forming a strip thereof, subjecting one side of said strip while the strip is wet to gas pressure with the other side subject to a lower gas pressure to remove liquid from and form open pores in said strip, and depositing granules upon the first-mentioned side of the strip, and squeezing said strip from opposite sides to force said granules into the pores of the strip and to press said fibers tightly around said granules.

5. The method comprising separating fibrous material from a mix of the order of liquid having cement and fibers remove liquid from and form open pores in said strip, and depositing granules upon the first-mentioned side of the strip, while the strip is soft and moist, and mechanically pressing said strip to force said granules into said pores and to squeeze the fibers and cement into tight contact with said granules.

6. In a machine for forming a continuous sheet or strip from a wet mix of the order of liquid having cement and fibers in suspension, the combination of a pressure tank, a hollow cylindrical drum rotatable in the pressure tank and having a foraminous circumferential wall to support a layer of said wet mix deposited on the outer surface of said wall and movable with the wall, means in said tank for applying a coating of a fluent surfacing substance upon the exposed surface of the deposited layer of material on said foraminous wall at a zone intermediate the length of the portion of said forarninous wall that is disposed within said tank, means to increase gas pressure within the tank substantially above atmospheric pressure at the side of said deposited layer opposite said foraminous wall and at opposite sides of said means for applying said coating to first force liquid from the deposited layer and from pores in said layer and then to force the surfacing substance of said coating into said pores of said deposited layer on said wall, and means for maintaining substantially lower gas pressure within said drum and at the side of said foraminous wall opposite said deposited layer.

7. In a machine for forming a continuous sheet or strip foraminous wall to support a layer posited on the upper surface of said wall and movable with the wall, means moving said wall through said chamber, means in said chamber for applying a coating of a fluent surfacing substance upon the exposed surface of the deposited layer of material on said foraminous wall at a zone intermediate the length of the portion of said foraminous wall that is disposed within said chamber, means to increase gas pressure within the chamber substantially above atmospheric pressure at the side of said deposited layer opposite said foraminous wall and at opposite sides of said means for applying said coating to first force liquid from the deposited layer and from pores in said layer and then to force the surfacing substance ly of said shoulders, and the first-named means including a vat having side walls each with one edge frictionally engaging one of said circumferential surfaces, a roller having a peripheral surface to engage said deposited layer with means forming liquid-tight joints between said roller, said shoulders and said side walls whereby the fluent surfacing substance can be contained between said deposited layer andsaid side walls and said roller, and as said deposited layer is caused to move with said foraminous wall due to rotation of the drum said fluent surfacing substance will be spread on said layer.

9. In amachine as defined in claim 7, the first-named means including a hopper for granular material and a chute leading from said hopper to a point above said foraminous wall and intermediate the length of the portion thereof that is exposed in said tank.

pressure into the pores of the deposited layer and thereafter the fibers of the deposited layer are squeezed around and into tight contact with the particles of the coating while the gas pressure is active.

References Cited in the file of this patent UNITED STATES PATENTS. 

1. THE METHOD COMPRISING SEPARATING AND FORMING A STRIP OF SOLID MATERIALS FROM A MIX OF THE ORDER OF LIQUID HAVING CEMENT AND FIBERS IN SUSPENSION, MOVING SAID STRIP WHILE THE STRIP IS WET THROUGH A PRESSURE CHAMBER WITH ONE SIDE EXPOSED TO THE ATMOSPHERE AND THE OTHER SIDE SUBJECTED TO A GAS PRESSURE SUBSTANTIALLY ABOVE ATMOSPHERIC PRESSURES TO FORCE LIQUID FROM SAID STRIP AND FORM PORES IN SAID STRIP, AND SPREADING A LAYER OF A WET MIX OF A SURFACING SUBSTANCE ON THE SECOND-MENTIONED SIDE OF SAID STRIP WHILE THE STRIP WITH SAID LAYER OF SURFACING SUBSTANCE THEREON IS MOVING THROUGH SAID PRESSURE CHAMBER THEREBY CAUSING SAID SURFACING SUBSTANCES TO FLOW INTO SAID PORES. 